# Letta

A platform for building stateful AI agents with long-term memory that can learn and improve over time, usable from a terminal, desktop and web apps, or a TypeScript SDK.

Letta, formerly known as MemGPT, is a platform for building stateful agents: AI with memory that can learn and improve over time. Its current source lives in a separate repository, which includes the agent harness, an interactive terminal UI, an app server, messaging channels, and the runtime behind its desktop and web apps.

It installs from npm and runs as an interactive terminal UI, or as an app server for local or self-hosted agents. It is also available as a desktop app for macOS, Windows and Linux, through a web app usable on mobile, through channels such as Slack, Telegram and Discord, or embedded in a TypeScript application through the Letta Agent SDK. Letta Cloud keeps an agent's memory, identity and conversations available across computers.

It is licensed under the Apache-2.0 license. An older V1 API server is kept on a separate archive branch for reproducibility, but current projects should use the newer source.

Website: https://docs.letta.com/